First Principles Calculation of Field Emission from Carbon Nanotubes With Nitrogen and Boron Doping

TL;DR

This study uses first principles calculations to analyze how nitrogen and boron doping affect the field emission properties of carbon nanotubes, revealing doping-dependent variations in emission current and charge cloud morphology.

Contribution

It provides novel insights into the effects of nitrogen and boron doping on carbon nanotube emission characteristics using advanced time-dependent density functional theory simulations.

Findings

Boron doping slightly enhances or impedes emission.

Nitrogen doping significantly influences emission current and charge cloud shape.

Nitrogenated nanotubes produce more diffuse charge clouds with branching.

Abstract

We investigate the field emission properties of nitrogenated and boronated carbon nanotubes using time-dependent density functional theory, were the wave function propagation is performed using the Crank-Nicholson algorithm. We extract the current-voltage characteristics of the emitted electrons from nanotubes with different doping configurations. We found that boron doping either impedes, or slightly enhances, field emission. Nitrogen strongly influences the emission current, and the current is sensitive to the location of the nitrogen dopant in the nanotube. The emitted charge cloud from nitrogen doped carbon nanotubes is, however, more diffuse than that from pristine ones, our simulations show the emergence of a branching from the charge cloud, making nitrogenated carbon nanotubes less convenient for use in narrow beam applications.